Shear Deformations of Slender Reinforced Concrete Walls under Seismic Loading. Paper by Katrin Beyer

to a large part of the stiffness degradation. 34,35 For calculation of the top displacement that corresponds to flexural yielding, the deformation in the web-shear mechanism should also be considered, together with the deformation in the flexural mechanism. In RC shear walls subjected to seismic loads, the flexural mechanism—both web shear and sliding shear—would be activated. These two shear deformations have high values, even in the case where the structural elements are designed to exhibit flexural behavior. It was found that in shear walls with a low aspect ratio, sliding shear deformations appear at the base plastic hinge, even in the case where the flexural behavior initially predominates the response. The displacement at the top of the walls due to the deformation of the sliding shear mechanism at the base of these walls was found to be significantly increased after the displacement ductility reached 2.5. 36 Hence, for the calculation of the top displacement ductility, the deformation of all load-resisting mechanisms, such as the flexural and shear mechanisms of the two, should be taken into account. Sliding shear displacements were not considered for the typical wall designs in the paper. It is not clear if the typical design was adopted for all walls studied or just for the U-shaped walls. The aspect ratio of the shear walls varies from 2.0 to 4.0 and no special joint detailing is illustrated. Can the authors demonstrate what detailing or criterion was used for these typical walls, where the sliding shear deformation can be neglected? For the calculation of the displacement ductility, the contribution of the shear mechanisms to the top displacement should be added to the inelastic deformations after yield. Does the ductility demand adopted in the analysis include the contribution of the shear deformation? AXIAL STRAINS’ DISTRIBUTION OVER CROSS SECTION